Collapsible loop aerial



July 16, 1929. M. MATHlEsEN GOLLAPSIBLE LOOP AERIAL Filed March 6, 1925 2 Sheets-Sheet l M. MATHlEsEN GOLLAPSIBLE LOOP AERIAL 2 Sheets-Sheet 2 Qfnv?? W' Mafzzzs Mai/21256@ Filed March 6, 1925 July 16, 1929. l

Patented July 16, 1929.

UNITED STATES @F165 v l s MARIUS MATHIESEN, 0F CHICAGO, ILLINOIS,A ASSIGNOR T0 MATIIIESEN-SANDBERG i COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

coLLArsIBLE Loop AERIAL.

Application'led March 6, 1925. Serial No. 13,598.

My invention relates to improvements in portable aerials of the loop form and has particular reference to an improved construction by which the loop can be readily collapsed for transportation and as readily extended for use. v

Such aerials usually comprise a mast and arms providing a frame upon which the aerial Ywire is wound in a plurality of turns.

A particular feature of my present invention relatesto simple means whereby a two part'mast` can readily be arranged in rigid extended form, the parts of the mast carrying arms hingedly connected thereto -so that they can be swung'in against the parts of the mast for` arranging the parts in a small compact arrangement for pack- 1n g and shipment.

A further feature relates Ato a simpleA means of'connecting the two parts of the mast to securely retain .them in end to end rigid extended condition and permit them to be readily' arranged in substantially parallel relation and occupying a minimum of space longitudinally.

Another feature relates to a novel manner of arranging 4the connecting wires whereby no loose ends are seen when the' device isset up and connected. v

Av further feature relates to the provision of a hollow support for the loop down through which the connecting ends of the loop wire are carried, in combination with stop means for preventing the rotation of the loop through more than one "revolution in each directiom Y Other advantages and features' of impor- Figure 11, is a perspective view of ra col-Y lapsible loop aerial embodying my inven-l` tion inone form;

Figure 2,is an elevational view of the frame work shown folded into a compact form; i

Figure 3, is a fragmentary, vertical, central, section on the line 3%-3 of Figure 1;

Figure 4, is a fragmentary, vertical, section on theline 4-4 of Figure 1;

Figure 5, is a yplan section on the line 5-5 of Figure l;`

Figure 6, is a fragmentary, elevational part of this specification` be mounted in vertical position on a spindle l4, which may be rigidly mounted in vertical position on a suitable base 5. The base 5 may represent a separate member or may represent a top panel or member. of a suitable radio cabinet, but in either case the spindle 4 is hollow so that the yends 6 of the wire 2- may be carried downlthrough the spindle below the base for convenience in connecting them with suitable binding posts 7 on the base or with the apparatus in the cabinet, as may be.

AThe frame 1 consists of va mast 8 upon which are hinged a plurality of arms, preferably tWo pairs of arms 9 and 10, one above the other, and the ends of the arms and the top and bottom of the mast are provided with l cross pieces 11 for receiving the several turns 3 of the aerial wire. Preferably the turns 3 of the wire are secured in a spaced relation on the cross pieces 11 by suitable cap members 12.

The `mast 8 consistsof two sections, an upper section 13 and a lower section 14,

and the lower section preferably has Vatubular reinforcing part 15 at its lower end. The lower pair' of arms 9 are hingedl to the power part 14 far enough from its lower end to permit them to swing down and in against the lower part 14 of the mast, as shown in Figure 2.

The upper pair of arms 10 are hinged to a short piece of tubing 17 which is slidable up and down on the mast, and whichrpart is limited in its downward movement by a stop pin 18 projecting from themast. The'arrangement is such that when the' sliding arm support 17 is at the lower limit of its Inovement the arms 10 are extended horizontally, and when this support is moved up the mastn the arms l()l are swung in against the upper part 13 of the mast, as shown in Figure 2.

The two parts 13 and 14 of the mast areV preferably rigidly connected in extended condition by means of a tubular doweling member 19 arranged at theiry adjacentendsand preferably rigidly secured on the upper end of the part 16 of the mast and projecting above same to provide a socket for receiving the lower end ot the upper part 13 of the mast. The turns 3 ot' the loop wire are tensioned when the 'frame is extended and this tensioning or' the turns hold the two parts of the mast tightly together.

The tensioning of the wire is accomplished by winding the wire on the 'frame with the upper pair of anms slightly collapsed, then when the support 17 is pushed down against the stop 18 the turns are tightly stretched. In collapsing the frame the upper pair of arms are irst swung in by pushing the support 17 upwardly, then the upper part 13 ot the mast can be lifted up out of the connecting socket and dropped down alongside the lower part 14 of the mast, asshown in Figure 2, at which time the lower pair of arms are swung down and in against the lower part 14 of the mast.

Asexplained hereinbefore, the spindle 4 is hollow and the ends of the loop wire are carried down through the spindle. They are thus out of sight and the device presents a very neat appearance. As the loop is rotatably mounted on the spindle for the purpose of permitting it to be readily set for attain-l ing the best results and as the ends 6 of the loop wire are out of sight, I provide simple means for preventing the rotation of the frame through more than one revolution, as otherwise the ends 6 might become damaged. This means consists of a stop pin 2() lixed to the lbase 5 and a second stop pin 21y projecting out from the lower end of the mast and adapted to contact with the pin 2() as the mast is rotated in either direction.

Instead of the doweling together of the two parts 13 and 14 of the mast I sometimes simply connect their adjacent ends together by a hinge 22, as shown in Figures 6 and 7 the upper part 13 beig free to be swung' down into parallel relation with the lower part 14. In the forms shown herein the frame work is collapsible into a compact bundle which is but slightly longer than onehalf the height of the extended Imast.

As many modifications of my invention will readily suggest themselves to one skilled in the art,"I do not limit or conline my invention to the specific details of construction herein described.

I claim:

1. In a collapsible loop aerial, a mast made of two parts adapted to be arranged in end to end abutting relation when the loop is extended, means for retaining the parts rigidly in loop extended position, arms hingedly mounted on the mast and adapted to be swung in parallel thereto when the loop is collapsed, the two parts of the mast adapted to be arranged substantially parallel to each other-and in a compact relation when the loop is collapsed. v

up of two separable parts adapted to be moved relatively endwise to ,extend or collapse the loop, a socket carried by one part for receiving an end of the other part for retaining the parts in y'extended relation, hinged arms carried by each part, cross arms ixed atthe ends of the mast and the arms, and an aerial wire wound in a plurality of spaced turns on said cross arms.

4L. In aV collapsible loop aerial, a two part mast, the parts adapted to be arranged fin end to end abutting relation when the loop is extended and in adjacent parallel relation substantially throughout their entire length when the loop is collapsed, means carried by one part for receiving the other part for retaining the abutting ends aga-inst relative sidewise movement, a pair ol.v arms hinged to one part, and a pair of arms hinged to a member slidably mounted on the other part, as and for the purpose described. i

5. In a loop antenna, a mast, and` upper and lower sets of wire loop supporting arms pivoted on said mast for movement outwardly to extended position and inwardly to folded position along the mast, crossV arms at the ends of the mast and arms, the outer ends of the arms being free of any rame connections, one of said sets movable longitudinally of the mast toward andI from the other set.

6. In a loop antenna, a mast, upper and lower wire loop supporting arms, disposed in,

substantially the same vertical plane, a wire loop carried by and fixed on said arms, the upper arms movable inwardly to collapse the loop and outwardly to reform the same,

A' the ends of the arms being free of connections except the antenna wire, and a sprlng controlled device for securing the upper arms in extended outward position on the mast forced outwardly against the wire loop to tighten and place the same under tension.

7. In a. vloop antenna, a mast, independent sets of wire loop supporting arms mounted on said mast disposed in substantially the same vertical plane, the ends of the arms being free. ofother connections except the antenna wire, androne of said sets of arms, movable longitudinally of the mast toward and from an adjacent set of saidarms.

8. In a loop antenna, a mast, independent sets of wire loop supporting arms mounted on said mast, a Wire receiving member on the mast, a wire loop carried on and around said arms and member, the outer ends of the arms being free of connections other than the antennal wire, one of said sets of arms movable longitudinal-ly along the mast to and from position to collapse said wire loop.

9. In a loop antenna, a base, a mast rotatably supported by the base, outwardly extending wire loop supporting arms pivoted to the lower portion of the mast for swinging inwardly therealong, a collar mounted for reciprocation on the upper portion of the mast, a pair of outwardly extending arms hinged to said reciprocating collar and normally disposed with their inner ends against said collar, said last mentioned'arms being adapted to move toward the mast axis, and toward each other, when said reciprocating'l collar is moved on the mast to cause relative swinging movement between said reciprocating collar and its associated arms, horizontally disposed cross members carried by the arms at their outer extremities and by the mast, and a wire loop carriedby said cross members and held tautly in loop forming position when said arms are in their extended positions, the outer ends of the arms being free of connections other than the antenna wire.

In testimony whereof, -I have hereunto set my hand, this 27th day of February, 1925.

MARIUS MATHIESEN. 

